Introduce copyinfrom and copyinstrfrom, which can copy data from either

user or kernel space.  This will allow layering of os-compat (e.g.: linux)
system calls.  Apply the changes to mount.

5 files changed, 67 insertions, 8 deletions

diff --git a/sys/kern/kern_subr.c b/sys/kern/kern_subr.c
index 6b51c5c..ac4bad6 100644
--- a/sys/kern/kern_subr.c
+++ b/sys/kern/kern_subr.c
@@ -387,3 +387,39 @@ uio_yield()
 	PICKUP_GIANT();
 	splx(s);
 }
+
+int
+copyinfrom(const void *src, void *dst, size_t len, int seg)
+{
+	int error = 0;
+
+	switch (seg) {
+	case UIO_USERSPACE:
+		error = copyin(src, dst, len);
+		break;
+	case UIO_SYSSPACE:
+		bcopy(src, dst, len);
+		break;
+	default:
+		panic("copyinfrom: bad seg %d\n", seg);
+	}
+	return (error);
+}
+
+int
+copyinstrfrom(const void *src, void *dst, size_t len, size_t *copied, int seg)
+{
+	int error = 0;
+
+	switch (seg) {
+	case UIO_USERSPACE:
+		error = copyinstr(src, dst, len, copied);
+		break;
+	case UIO_SYSSPACE:
+		error = copystr(src, dst, len, copied);
+		break;
+	default:
+		panic("copyinstrfrom: bad seg %d\n", seg);
+	}
+	return (error);
+}
diff --git a/sys/kern/vfs_extattr.c b/sys/kern/vfs_extattr.c
index 178d2a2..709736c 100644
--- a/sys/kern/vfs_extattr.c
+++ b/sys/kern/vfs_extattr.c
@@ -107,12 +107,21 @@ struct mount_args {
 int
 mount(p, uap)
 	struct proc *p;
-	register struct mount_args /* {
+	struct mount_args *uap;
+{
+	return (mount1(p, uap, UIO_USERSPACE));
+}
+
+int
+mount1(p, uap, segflag)
+	struct proc *p;
+	struct mount_args /* {
 		syscallarg(char *) type;
 		syscallarg(char *) path;
 		syscallarg(int) flags;
 		syscallarg(caddr_t) data;
 	} */ *uap;
+	int segflag;
 {
 	struct vnode *vp;
 	struct mount *mp;
@@ -140,8 +149,7 @@ mount(p, uap)
 	/*
 	 * Get vnode to be covered
 	 */
-	NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_USERSPACE,
-	    SCARG(uap, path), p);
+	NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, segflag, SCARG(uap, path), p);
 	if ((error = namei(&nd)) != 0)
 		return (error);
 	NDFREE(&nd, NDF_ONLY_PNBUF);
@@ -209,7 +217,8 @@ mount(p, uap)
 		vput(vp);
 		return (ENOTDIR);
 	}
-	if ((error = copyinstr(SCARG(uap, type), fstypename, MFSNAMELEN, NULL)) != 0) {
+	if ((error = copyinstrfrom(SCARG(uap, type),
+	     fstypename, MFSNAMELEN, NULL, segflag)) != 0) {
 		vput(vp);
 		return (error);
 	}
diff --git a/sys/kern/vfs_syscalls.c b/sys/kern/vfs_syscalls.c
index 178d2a2..709736c 100644
--- a/sys/kern/vfs_syscalls.c
+++ b/sys/kern/vfs_syscalls.c
@@ -107,12 +107,21 @@ struct mount_args {
 int
 mount(p, uap)
 	struct proc *p;
-	register struct mount_args /* {
+	struct mount_args *uap;
+{
+	return (mount1(p, uap, UIO_USERSPACE));
+}
+
+int
+mount1(p, uap, segflag)
+	struct proc *p;
+	struct mount_args /* {
 		syscallarg(char *) type;
 		syscallarg(char *) path;
 		syscallarg(int) flags;
 		syscallarg(caddr_t) data;
 	} */ *uap;
+	int segflag;
 {
 	struct vnode *vp;
 	struct mount *mp;
@@ -140,8 +149,7 @@ mount(p, uap)
 	/*
 	 * Get vnode to be covered
 	 */
-	NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_USERSPACE,
-	    SCARG(uap, path), p);
+	NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, segflag, SCARG(uap, path), p);
 	if ((error = namei(&nd)) != 0)
 		return (error);
 	NDFREE(&nd, NDF_ONLY_PNBUF);
@@ -209,7 +217,8 @@ mount(p, uap)
 		vput(vp);
 		return (ENOTDIR);
 	}
-	if ((error = copyinstr(SCARG(uap, type), fstypename, MFSNAMELEN, NULL)) != 0) {
+	if ((error = copyinstrfrom(SCARG(uap, type),
+	     fstypename, MFSNAMELEN, NULL, segflag)) != 0) {
 		vput(vp);
 		return (error);
 	}
diff --git a/sys/sys/mount.h b/sys/sys/mount.h
index 77ee4e5..ea5a71a 100644
--- a/sys/sys/mount.h
+++ b/sys/sys/mount.h
@@ -312,6 +312,7 @@ extern struct vfsconf *vfsconf;	/* head of list of filesystem types */
 #ifdef __STDC__
 struct nameidata;
 struct mbuf;
+struct mount_args;
 #endif
 
 struct vfsops {
@@ -403,6 +404,7 @@ extern	char *mountrootfsname;
  * exported vnode operations
  */
 int	dounmount __P((struct mount *, int, struct proc *));
+int	mount1 __P((struct proc *p, struct mount_args *uap, int segflag));
 int	vfs_setpublicfs			    /* set publicly exported fs */
 	  __P((struct mount *, struct netexport *, struct export_args *));
 int	vfs_lock __P((struct mount *));         /* lock a vfs */
diff --git a/sys/sys/uio.h b/sys/sys/uio.h
index a2de90a..547dbad 100644
--- a/sys/sys/uio.h
+++ b/sys/sys/uio.h
@@ -79,6 +79,9 @@ struct vm_object;
 int	uiomove __P((caddr_t, int, struct uio *));
 int	uiomoveco __P((caddr_t, int, struct uio *, struct vm_object *));
 int	uioread __P((int, struct uio *, struct vm_object *, int *));
+int	copyinfrom __P((const void *src, void *dst, size_t len, int seg));
+int	copyinstrfrom __P((const void *src, void *dst, size_t len,
+	    size_t *copied, int seg));
 
 #else /* !_KERNEL */